New galactic star clusters discovered in the VVV survey. Candidates projected on the inner disk and bulge

Context. VISTA Variables in the Vía Láctea (VVV) is one of six ESO Public Surveys using the 4 meter Visible and Infrared Survey Telescope for Astronomy (VISTA). The VVV survey covers the Milky Way bulge and an adjacent section of the disk, and one of the principal objectives is to search for new star clusters within previously unreachable obscured parts of the Galaxy. Aims. The primary motivation behind this work is to discover and analyze obscured star clusters in the direction of the inner Galactic disk and bulge. Methods. Regions of the inner disk and bulge covered by the VVV survey were visually inspected using composite JHKS color images to select new cluster candidates on the basis of apparent overdensities. DR1, DR2, CASU, and point spread function photometry of 10 × 10 arcmin fields centered on each candidate cluster were used to construct color–magnitude and color–color diagrams. Follow-up spectroscopy of the brightest members of several cluster candidates was obtained in order to clarify their nature. Results. We report the discovery of 58 new infrared cluster candidates. Fundamental parameters such as age, distance, and metallicity were determined for 20 of the most populous clusters.

Photogeneration of Hydrogen from Water by Hybrid Molybdenum Sulfide Clusters Immobilized on Titania

Two new hybrid molybdenum(IV) Mo3S7 cluster complexes derivatized with diimino ligands have been prepared by replacement of the two bromine atoms of [Mo3S7Br6]2− by a substituted bipyridine ligand to afford heteroleptic molybdenum(IV) Mo3S7Br4(diimino) complexes. Adsorption of the Mo3S7 cores from sample solutions on TiO2 was only achieved from the diimino functionalized clusters. The adsorbed Mo3S7 units were reduced on the TiO2 surface to generate an electrocatalyst that reduces the overpotential for the H2 evolution reaction by approximately 0.3 V (for 1 mA cm−2) with a turnover frequency as high as 1.4 s−1. The nature of the actual active molybdenum sulfide species has been investigated by X-ray photoelectron spectroscopy. In agreement with the electrochemical results, the modified TiO2 nanoparticles show a high photocatalytic activity for H2 production in the presence of Na2S/Na2SO3 as a sacrificial electron donor system.

Clusters de las Tecnologías de la Información y la Comunicación, Desempeño de las Empresas Locales y Generación de Empleos en Córdoba

Un argumento conocido es que las tecnologías de la información y las comunicaciones (TIC) han creado una brecha digital creciente entre las economías maduras y la de los países de menor desarrollo relativo. A su vez, se plantea con carácter de paradigma, que esta tendencia podría revertirse con la incorporación de incentivos al desarrollo local de industrias TIC en los países menos desarrollados. En los últimos años muchos gobiernos de países en vías de industrialización prestan creciente atención al desarrollo de industrias TIC en sus territorios. En esa promoción se observa, sin embargo, la persistencia de un viejo debate sobre las opciones de aplicar un fuerte “impulso masivo”, o impulsos “hacia adelante” y “hacia atrás”. Por ello resulta de gran interés el estudio de casos exitosos de desarrollo local de empresas TIC que permitan interpretar la naturaleza de las políticas de promoción y el impacto en cuanto a: (i) generación y fortalecimiento de eslabonamientos, con los proveedores, por un lado, y con la demanda, por el otro, (ii) diferenciación según el carácter nacional o multinacional de las empresas impulsoras, (iii) papel de las universidades e institutos de investigación, (iv) efectos sobre la generación de empleo directo e indirecto. Esta propuesta asume que existe la necesidad de comprender mejor el impacto del desarrollo local de ofertas TIC, la interrelación entre firmas locales, firmas locales y multinacionales y entre todas estas, y la capacidad doméstica de investigación, desarrollo e inversión. Un corpus de conocimiento de esta naturaleza es indispensable para que los responsables puedan diseñar las políticas públicas de incentivos adecuadas para generar los estímulos apropiados y contribuir al fortalecimiento del sector. Bajo este enfoque, es que el objetivo general del proyecto es investigar el impacto, en Córdoba, del paradigma TIC en la generación de una oferta local de firmas que elaboran productos y desarrollan servicios TIC, a partir de decisiones empresariales independientes, o como parte de una cadena productiva en la cual interviene una variedad de firmas locales e internacionales. La investigación estará centrada, por una parte, en el estudio de la evolución de los ordenamientos institucionales y legales para la promoción del sector TIC en el país y en Córdoba, y, por la otra, se focalizará en el análisis de los datos de fuente primaria sobre las firmas radicadas en el Gran Córdoba, que elaboran productos y desarrollan servicios TIC. El abordaje conjunto de ambos planos de análisis, permitirá contrastar la principal hipótesis de investigación que postula que, si se proveen entornos adecuados, orientados a facilitar los medios para superar las restricciones económicas, sociales, legales e institucionales, es posible lograr el desarrollo de cadenas productivas de firmas TIC, que generan impacto positivo en el medio local – principalmente el empleo - e integran a firmas domésticas y multinacionales, a centros de investigación, e incluso, a organizaciones de consumidores. Una segunda hipótesis a ser contratada en el trabajo, es que el desarrollo TIC en la provincia de Córdoba respondió a una estrategia de fuerte impulso masivo y servirá como evidencia empírica que contribuya al debate teórico sobre el tema. En la metodología se prevé realizar una recopilación de datos de fuentes secundarias del sector público y privado, a partir de la cual se elaborará un marco general para llevar a cabo la recolección de datos de fuentes primarias, mediante un conjunto de entrevistas en profundidad a informantes calificados y una encuesta a empresas TIC, nacionales y multinacionales, radicadas en el Gran Córdoba. El tratamiento y análisis de los datos comprenderá la elaboración de tablas, gráficos y cálculo de correlaciones e indicadores descriptivos, como así también la aplicación de modelos econométricos de riesgo y de supervivencia con fines predictivos. Los procesamientos se realizarán con el soft STATA.

Desenvolvimento económico baseado na teoria dos Clusters: o exemplo do calçado em Portugal

Este trabalho aborda o tema dos clusters industriais - concentrações geográficas de empresas interligadas, fornecedores de produtos e serviços, empresas em setores afins e entidades que lhes estão associadas, como as universidades, entidades públicas, associações empresariais. A competitividade resulta da ação das empresas, e estas devem competir e cooperar para criar lucro económico, mas também gerar benefícios para a região e o país. O objetivo deste trabalho é demonstrar que a aplicação da teoria dos clusters no nosso país, - introduzida na sequência de um estudo pedido em 1994 ao criador desta teoria, o Dr. Michael Porter – teve efeitos muito positivos no desenvolvimento dos últimos 20 anos e que maiores poderiam ter sido esses efeitos, se tivesse sido feita a sua aplicação em todos os setores em que se identificavam vantagens competitivas da nossa economia. Foi realizada uma análise da evolução do mais reconhecido cluster, o da indústria do calçado, cujos resultados apontam para as estratégias a adotar em muitos outros setores da nossa economia. Numa extrapolação, fica claro que as regiões nacionais e os países que contam com clusters industriais são aqueles que apresentam desempenho superior, em termos de intensidade exportadora e valor acrescentado. Estas zonas apresentam ainda níveis elevados de riqueza e longevidade dos seus cidadãos. Em termos europeus, a Alemanha, que tem como grandes clusters os setores automóvel, da automação, da eletrónica e da pesquisa laboratorial, é o melhor exemplo deste facto.

Do Clusters Generate Greater Innovation and Growth? An Analysis of European Regions. Bruges European Economic Research (BEER) Papers 21/October 2011

The analysis of clusters has attracted considerable interest over the last few decades. The articulation of clusters into complex networks and systems of innovation -- generally known as regional innovation systems -- has, in particular, been associated with the delivery of greater innovation and growth. However, despite the growing economic and policy relevance of clusters, little systematic research has been conducted into their association with other factors promoting innovation and economic growth. This article addresses this issue by looking at the relationship between innovation and economic growth in 152 regions of Europe during the period between 1995 and 2006. Using an econometric model with a static and a dynamic dimension, the results of the analysis highlight that: a) regional growth through innovation in Europe is fundamentally connected to the presence of an adequate socioeconomic environment and, in particular, to the existence of a well-trained and educated pool of workers; b) the presence of clusters matters for regional growth, but only in combination with a good ‘social filter’, and this association wanes in time; c) more traditional R&D variables have a weak initial connection to economic development, but this connection increases over time and, is, once again, contingent on the existence of adequate socioeconomic conditions.

Forms and role of the cluster initiatives in fostering innovation in post-industrial regions: A comparative study of environmental clusters in British West Midlands and Spanish Basque country. ACES Working Paper No. 8, August 2008

The objective of this research is to present cluster initiative approaches in post industrial regions characterized by similar economic history and challenges, with additional emphasis on their role in promoting innovation among regional businesses. The research is based on a comparison study of two environmental industry clusters: Environmental Technology Cluster (ET) from British West Midlands and ACLIMA from Spanish Basque Country. The study analyzes clusters' design and their role in fostering innovation based on environment industry clusters. In both regions environmental industry clusters represent strong potential for further dynamic development with grow opportunities driven by legislation introduced at EU, national or regional levels. The paper compares clusters' heterogeneity, goals and priorities, financing schemes, management structure, types of projects, character of private-public partnerships, challenges, as well as clusters' collaboration at regional/national/international levels. Also focus is given on how the clusters enhance innovation and what types of projects are executed by the regions in this field.

Market clusters for international franchising. ACES Working Papers, August 2009

While many studies of franchising have examined the organizational antecedents of internationalization, few have examined how differences among markets lead to this internationalization. Studies linking environmental factors to the companies' decision to internationalize showed that various political, social and economic factors either attract or repel international franchising investment. We build on these studies' selected variables to understand the similarities and differences among international franchising markets. Using these variables, our results show that countries divide into eight clusters with similar international franchising market characteristics. A discussion of each cluster follows with implications for franchising research.

Changing cultural clusters: A research note. ACES Working Papers, August 2009

The purpose of this research note is to investigate the changing cultural clusters that emerged between the studies of Hofstede (1970s) and GLOBE (1990s) using similar measures and overlapping countries. Our study analyzes the world's cultural clusters using two seminal and comparable cultural classifications: Hofstede and GLOBE. Four common cultural dimensions are empirically examined: individualism, power distance, uncertainty avoidance, and masculinity. We use two leading methods from cluster analysis and display data in both dandrograms and pie chart forms showing the grouping of countries. Our results suggest diverging cultural typologies that transcend geography, language, and religion. Countries are engaged in selective cultural borrowing that leads to new and changing global cultural structures.

Using multiple landscape genetic approaches to test the validity of genetic clusters in a species characterized by an isolation-by-distance pattern

Bayesian clustering methods are typically used to identify barriers to gene flow, but they are prone to deduce artificial subdivisions in a study population characterized by an isolation-by-distance pattern (IbD). Here we analysed the landscape genetic structure of a population of wild boars (Sus scrofa) from south-western Germany. Two clustering methods inferred the presence of the same genetic discontinuity. However, the population in question was characterized by a strong IbD pattern. While landscape-resistance modelling failed to identify landscape features that influenced wild boar movement, partial Mantel tests and multiple regression of distance matrices (MRDMs) suggested that the empirically inferred clusters were separated by a genuine barrier. When simulating random lines bisecting the study area, 60% of the unique barriers represented, according to partial Mantel tests and MRDMs, significant obstacles to gene flow. By contrast, the random-lines simulation showed that the boundaries of the inferred empirical clusters corresponded to the most important genetic discontinuity in the study area. Given the degree of habitat fragmentation separating the two empirical partitions, it is likely that the clustering programs correctly identified a barrier to gene flow. The differing results between the work published here and other studies suggest that it will be very difficult to draw general conclusions about habitat permeability in wild boar from individual studies.

Self-tuning for cloud database clusters

Otto-von-Guericke-Universität Magdeburg, Fakultät für Informatik, Dissertation, 2016

Commentary on interstellar matter associated with 18 open clusters /

"September 1989"--Cover.

A new general catalogue of nebulae and clusters of stars, being the catalogue of the late Sir John F.W. Herschel.

Mode of access: Internet.

Uranography ; or, a description of the heavens; designed for academies and schools; accompanied by an atlas of the heavens, showing the places of the principal stars, clusters, and nebulæ /

Mode of access: Internet.

On a resampling approach for tests on the number of clusters with mixture model-based clustering of tissue samples

We consider the problem of assessing the number of clusters in a limited number of tissue samples containing gene expressions for possibly several thousands of genes. It is proposed to use a normal mixture model-based approach to the clustering of the tissue samples. One advantage of this approach is that the question on the number of clusters in the data can be formulated in terms of a test on the smallest number of components in the mixture model compatible with the data. This test can be carried out on the basis of the likelihood ratio test statistic, using resampling to assess its null distribution. The effectiveness of this approach is demonstrated on simulated data and on some microarray datasets, as considered previously in the bioinformatics literature. (C) 2004 Elsevier Inc. All rights reserved.

Ultra-compact dwarf galaxies in galaxy clusters

We review the evidence that the ultra-compact dwarf (UCD) galaxies we recently discovered in the Fornax Cluster form a new, previously unknown class of galaxies and we discuss possible scenarios for their formation. We then present recent results that UCDs are also present in the Virgo Cluster, and that there is a much larger than expected population of fainter UCDs in the Fornax Cluster. The size and properties of this population may lead us to revise our original 'galaxy threshing' hypothesis for the formation of UCDs.